A METHOD OF CHARACTERISING PHYSICAL PROPERTIES OF AN ATTENUATING ELEMENT IN A RADIOTHERAPY DEVICE

摘要

Disclosed herein is a method of characterising physical properties of an attenuating element in a radiotherapy device having a radiotherapy radiation source and a radiotherapy radiation detector on respective sides of the attenuating element. The method comprises obtaining an average detected radiotherapy radiation intensity at two or more locations around the attenuating element, comparing the detected intensity at one location with the average intensity, and characterising a corresponding physical property based on the comparison.